It is difficult to diagnose early metastatic disease from squamous cell carcinoma of the upper aerodigestive tract in patients who have no clinical evidence of regional disease on examination. In fact, a significant proportion of patients harbor occult cervical metastases that are undetected by physical exam and current radiographic techniques. The objective of this study is to use lymphoscintigraphy and gamma-probe guided surgery to localize the sentinel node in the neck of patients with squamous cell carcinoma of the upper aerodigestive tract. This technique has been successfully implemented for specific indication in breast cancer and melanoma. Pilot data will be gathered on patients with T1 and T2 squamous cell carcinomas of the upper aerodigestive tract whose tumors are accessible for injection and are to have a selective neck dissection as part of their planned treatment. The primary tumor site will be injected with unfiltered Technetium Tc 99m Sulfur Colloid on the day prior to surgery and the sentinel node(s) will be located by the gamma probe and removed subsequently at the time of tumor resection and neck dissection. The histopathology of the sentinel node(s) will be correlated with the histopathological status of the remainder of the lymph nodes. The sensitivity and predictive value of the sentinel node for predicting the status of other nodes in the neck will be evaluated. If sentinel node is an effective marker for the presence of other cervical metastatic disease, the morbidity of an elective neck dissection could be avoided in patients with clinically negative exam and negative sentinel lymph node. This approach could significantly reduce the morbidity of treatment while still obtaining tissue for histopathological evaluation and molecular analysis.